Constituents of the stem bark of Dombeya rotundifolia Hochst

Two compounds isolated from Dombeya rotundifolia chloroform stem bark extract were identified as lupeol and β-sitosterol using infra red, nuclear magnetic resonance and mass spectrometry. The East and Central African Journal of Pharmaceutical Sciences Vol. 8(2) 2005: 40-4

Phytosterols from the stem bark of Combretum fragrans F. Hoffm

Two sterols, β-sitosterol and stigmasterol, were isolated from the stem bark of Combretum fragrans. The identity of these compounds was established by spectral analysis

Phytosterols from Dombeya torrida (J. F. Gmel.)

Dombeya torrida collected from Kinale forest in Kiambu County, Kenya, was Soxhlet extracted with chloroform and by percolation using a  dichloromethane:methanol mixture. The extracts were fractionated using normal phase silica gel in an open column. Five compounds were isolated namely friedelin, friedelan-3β-ol, α-sitosterol, taraxerol and stigmasterol. This is the first report of isolation of these compounds from Dombeya torrida. The isolated compounds were identified by means of 1H-NMR, 13C-NMR, DEPT, MS and IR analyses.Key words: Dombeya torrida, friedelin, friedelan-3β-ol, β-sitosterol, stigmasterol, taraxerol

Anthelmintic and Antibacterial Activity of Hagenia abyssinica (Bruce) J.F. Gmel (Rosaceae)

Organic solvent extracts of the stem bark of Hagenia abyssinica Bruce J.F. Gmel (Rosaceae) were screened for anthelmintic and antibacterial activity. The methanol and dichloromethane/methanol extracts exhibited anthelmintic activity when tested using Panagrellus redivivus model. Further, the stem bark methanol extract showed significant but weaker activity than levamisole against Caenorhabditis elegans species. The petroleum ether and the dichloromethane/methanol extracts exhibited significant antibacterial activity against Staphylococcus aureus, Bacillus subtilis and Escherichia coli at a concentration of 50 mg/ml, but no antifungal activity.Key words: Hagenia abyssinica, anthelmintic, antibacteria

Quality Performance of Drugs Analyzed in the Drug Analysis and Research Unit (DARU) during the Period 2006-2010

During the period 2006-2010, the Drug Analysis and Research Unit analyzed 583 samples. The samples comprised 50.6% local and 49.4% imported products. Samples were subjected to compendial or in-house specifications. The failure rate was 12.2% for local products and 14.2% for imports.  Antibacterial products recorded the highest failure rate (21.6%) while  anticancers and drugs acting on the gastrointestinal, respiratory and  reproductive systems all passed in the tests performed. The failure rate for antiprotozoals, antimalarials, antifungals, anthelminthics and analgesics was 14.3%, 12.5%, 11.8%, 8.9% and 11.5%, respectively.Key words: DARU, drug product, assay, dissolution, antimicrobial, antimalaria

Antimicrobial properties of some medicinal plants of the Luo community of Kenya

Background: The Luo community of Kenya rely mostly on ethno-medicine to manage human ailments. This study was set to survey, record and report the medicinal plant species they use to manage infectious conditions. Objective of this study was to screen the plants used by this community to treat microbial infections, to demonstrate their in-vitro antibacterial and antifungal activities. Methodology: Eight plants namely Lannea stuhlmanii, Carissa edulis, Combretum fragrans, Conyza sumatrensis, Ormocarpum trichocarpum, Sida cuneifolia, Plumbago zeylanica, and Rhoicissus revoilii, used by the Luo for treatment of microbial infections, were studied. Observations and semi-structured interviews were used to gather ethno-botanical data for each plant. About 3 kg of suitable specimens were harvested, with leaves pressed and preserved for identification at University of Nairobi’s Department of Botany Herbarium. Voucher specimens were also deposited at the University’s School of Pharmacy Herbarium and excess material powdered and kept dry. The pressed specimens were dried at 20 0C to 25 0C using plant blower. Their ethanolic extracts were screened for their antimicrobial activity against Candida albicans, Escherichia coli, Staphylococcus aureus and Bacillus pumulus. Results: Extracts from Conyza sumatrensis, C. fragrans, C. edulis, S. cuneifolia, R. revoilii and leaf C. sumatrensis had good activity against E. coli. Activity against B. pumulus was observed in all extracts except those of L. stuhlmanii bark and R. revoilii tubers. Good activity against S. aureus was observed with C. fragrans, S. cuneifolia and L. stuhlmanii. Rhoicissus revoilii, L. stuhlmanii, C. fragrans and C. edulis exhibited good antifungal activity against Candida albicans. Conclusion: This work partially supports the traditional antimicrobial use of the various plants, and it is hoped that the results will form the basis for further research that could lead to isolation and/or development of antibacterial and antifungal medicines for use in primary health care. The results also confirm that plants are a potential source of antimicrobial compounds